Combined hearing aid volume control knob and adapter ring



FIG. 1 is a perspective view of a combined hearing aid volume control knob and adapter ring showing my new design;

FIG. 2 is a side view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

The dot and dash line portions of the drawing are included to show environmental structure not claimed as part of my ornamental design. 

The ornamental design for a combined hearing aid volume control knob and adapter ring, as shown and described. 